serial dilutions Flashcards
1
Q
why is a serial dilution carried out?
A
- too many colonies merge together
- makes it impossible to count
- so reduces population density
2
Q
summarise how the serial would be carried out?
A
- 10cm3 broth in one tube
- take 1cm3 and add to 9cm3 distilled water
- take 1cm3 of the second sample and add to 9cm3 distilled water
- repeat
- a drop is placed on an agar plate
3
Q
how is population density calculated?
A
- count colonies
- multiply by dilution factor
- multiply by volume